Adhesive cotton article and method of making same



May 22, 1956 G. 1.. DENISTON ADHESIVE COTTON ARTICLE AND METHOD OFMAKING SAME Original Filed Aug. 14, 1951 INVENTOR GEORGE L. DENISTONATTORNEYS ADHESIVE @GTTUN ARTHILE AND METHGD GF MAKING George L.Deniston, Dayton, (lhio, assignor to The (loinmonwealth EngineeringCompany of @hio, Dayton, @hio, a corporation of @hio Originalapplication August 114, 1951, Serial No. 241,740, now Patent No.greases, dated Aprii 19, 1955. Di vided and this appiication September22, 1952, Serial No. 3319304 12 Claims. (Q3. 117--63) This inventionrelates to a process of treating cotton threads, yarns and fabrics withdextran and its derivatives and to the products produced thereby.

This application is a division of application Serial No. 241,740, filedAugust 14, 1951, now U. S. Patent Serial No. 2,706,690, and assigned tothe same assignee as the present invention.

Dextran is a water soluble colloidal material produced by the action ofmicroorganisms on sucrose bearing materials and may be converted intodextran ethers and esters as described in U, S. Patents 2,344,179,2,203,702 and 2,385,553.

This invention contemplates the provision of a novel process for theimpregnation and coating of cotton materials with dextran and itsderivatives.

The invention contemplates the provision of a new product wherein cottonprovides a strength core and material impregnated therein and coatedthereon provides an outer shell resistant to ordinary chemical attackbut which may be rendered sufficiently tacky by selected solvents forthe seeming of good adhesions in many materials of commerce.

More particularly, in the process of invention cotton in the form of athread, yarn or fabric is treated with dextran, dissolved in a solvent,to secure penetration of the dextran into the fibers, and thereafter thedextran bearing cotton is treated with an alkylating agent in analkaline solution and then subjected to a heating step to form a productresistant to chemical action but selectively attacked by particularsolvents. An additional feature of the process, particularly as relatedto commercial yarn and fabrics as used in rubber and plastic industries,is the substantial elimination of residual stretch therefrom by theheating of the composite body under tensive conditions.

While i prefer to use a combination of sodium hydroxide and water as thedextran solvent, due to the efficiency of this combination the effectingof a swelling of the cotton fibers to thereby permit maximum penetrationof the dextran, other solvents, e. g. water alone, water and sodiumcarbonate, a dilute acetic acid solution or dilute solutions of themineral acids such as HCl and H2804 may suitably be employed.

The alkylating agent for the dextran, which is utilized to substitute oradd an alkyl group into the dextran, may include: the organic halidessuch as methyl, ethyl, propyl; isopropyl or benzyl halides; the alkylsulphates such as diethyl sulphate; tri-ethyl phosphate; and arylsulfonic alkyl esters such as the ethyl ester of p-toluene sulfonicacid.

The alkylating agent is employed in alkaline solution this alkali ispreferably sodium or potassium hydroxide, sodium carbonate or an organicalkali.

T he product of the process of invention may comprise, for example, adestretcied yarn having the cotton core surrounded by the benzyl etherof dextran which is insoluble in and substantially unaffected by H2O,alkalis, mineral acids, and the lower aliphatic alcohols, but which whentreated with acetone, dioxane, benzene or toluene atent becomes tacky.Thus this destretched yarn has a particular utility in powertransmission belt structures where it may be laminated with rubber andcured thereto. Similarly a fabric treated by the process of inventionattains qualities suitable for lamination with resinous materials.

The invention will be more fully understood by reference to thefollowing specific examples and the drawing wherein:

Figure l of invention;

Figure 2 is a view of the grooved roller in Figure 1;

Figure 3 is a partial plan view of the apparatus of Figure 1; and

Figure 4 is a plan view of the grooved tapered roller shown in the ovenof Figure 1.

illustrates the apparatus used in the process Example I There is shownin Figure 1 a tank or vat 1 containing a dextran solution 2, thesolution containing by weight approrimately 40% dextran of any molecularweight, 55% water and about 5% of sodium hydroxide. A cotton yarn 3 isshown passing continuously from bobbin 4, mounted on roll 5, into thesolution 2 Where it is guided between rolls 6 and '1', which are adaptedto be driven independently by means not shown at speeds differing byabout 30%, the roll 7 having the greater velocity. The rolls 6 and 7 aremulti-grooved as shown in Figure 2 in order that the time of passage ofthe yarn through the solution may be readily controlled, by utilizationof a selected number of grooves for particular size yarns.

The yarn is shown in Figure l as passing from solution 2 over roll 8into bath 9 containing alkaline aralkyl halide solution 19 having byweight approximately 30% of benzyl chloride, 9% of sodium hydroxide and61% water. The wetted and impregnated yarn 3 passes over rolls 20 and 21which are grooved similarly to rolls 6 and 7 and after a multi passthrough the solution, as more clearly shown in Figure 3, enters a heatedoven 12 over roller 31. A hollow conical die 13 is positioned betweenbath 9 and oven 12 to remove any excess material present on the yarnbefore it passes to the heating operation,

The oven 12 is provided with grooved rollers 14, 15, roller 15 beingdriven at a speed about 30% in excess of that of roller 14, and theroller 15 having grooves of progressively (Figure 4) increasingdiameter, from end 16 to end 17, to facilitate the destretching of theyarn. After curing the yarn is wound up on coil 18 mounted on stand 19.

When impregnating and coating the yarn is passed through bath 2 undertension if desired although the same is not necessary but does assist inthe ultimate de-stretching of the yarn and the dextran pick up issomewhat greater if tension is employed. In solution 10 the dextran andaralkyl halide initiate a reaction which is completed in oven heater 112at temperatures of about to C.

The finished product has substantially no stretch retained therein anddue to the coating resists moisture thus preventing shrinkage effectsfrom occurring in the yarn rendering the product particularly usefulwhere constant yarn length under varying humidity conditions isessential. Since the productis also resistant to alcohols, the mineralacids, and alkalis, it may be employed under conditions where suchresistance is beneficial.

it will be clear from the foregoing that the degree of impregnation ofthe yarn may be controlled by controlling the solution concentrationsparticularly the dextran. Furthermore a coating may be applied over theyarn to completely sheath the same by utilizing viscous solution.

Example 11 The apparatus described in connection with Example I may bereadily modified to permit the coating of a cotton fabric with an ethyldextran which is resistant to water, the mineral acids, and alkalis, butsoluble in the alcohols.

The dextran may in this instance be solved in a weak sodium hydroxide,and an efiicient mixture would contain:

50% dextran 40% water sodium hydroxide The fixing solution may contain:

50% (ii-ethyl sulphate 30% water sodium hydroxide The procedure isessentially the same as set forth in Example I, the heating temperaturehowever being of the order of 100115 C.

It will be understood that while there have been given herein certainspecific examples of the practice of this invention, it is not intendedthereby to have this invention limited to or circumscribed by thespecific details of materials, proportions or conditions hereinspecified, in view of the fact that this invention may be modifiedaccording to individual preference or conditions Without necessarilydeparting from the spirit of this disclosure and the scope of theappended claims.

I claim:

1. An adhesive yarn consisting of a cotton core impregnated and coatedwith a substance selected from the group consisting of alkyl and aralkylethers of dextran, said core being set in substantially non-stretchablecondition by the dextran ether, and said ether being in adhesivecondition in and on the core as a result of solvent treatment thereof insitu in the yarn.

2. Au adhesive yarn consisting of a cotton core irnpregnated and coatedwith an ethyl ether of dextran, said core being set in substantiallynon-stretchable condition by the dextran ether, and said ether being inadhesive condition in and on the core as a result of solvent treatmentthereof in situ in the yarn.

3. An adhesive yarn consisting of a cotton core impregnated and coatedwith a benzyl ether of dextran, said core being set in substantiallynon-stretchable condition by the dextran ether, and said ether being inadhesive condition in and on the core as a result of solvent treatmentthereof in situ in the yarn.

4. A fabric comprising adhesive yarns consisting of a cotton core coatedand impregnated with a substance selected from the group consisting ofalkyl and aralkyl ethers of dextran, said core being set insubstantially nonstretchable condition by the dextran ether, and saidether being in adhesive condition in and on the core as the result ofsolvent treatment thereof in situ in the fabric.

5. A power transmission belt comprising yarns con-sisting of a cottoncore coated and impregnated with a substance selected from the groupconsisting of alkyl and aralkyl ethers of dextran, said core being setin substantially non-stretchable condition by the dextran ether, andsaid ether being in adhesive condition in and on the core as the resultof solvent treatment thereof in situ in the belt.

6. A power transmission belt comprising yarns consisting of a cottoncore coated and impregnated with a benzyl ether of dextran, said corebeing set in substantial- 1y non-stretchable condition by the dextranether, and said ether being in adhesive condition in and on the core asthe result of solvent treatment thereof in situ in the belt.

7. The method of producing an adhesive cotton yarn which comprisestreating a cotton yarn with an aqueous alkaline solution of dextran,then treating the dextran-impregnated cotton yarn with an aqueousalkaline solution of an etherifying agent selected from the groupconsisting of alkylating and aralkylating agents, heating theimpregnated yarn to complete reaction between the etherifying agent andthe dextran in situ in the yarn, and thereafter treating the yarn with asolvent for the dextran ether to activate the ether to adhesivecondition.

8. The method of producing an adhesive cotton yarn which comprisestreating a cotton yarn with an aqueous alkaline solution of dextran,then treating the dextranimpregnated cotton yarn with an aqueousalkaline solution of a benzyl ether of dextran, heating the impregnatedyarn to a temperature of C. to C. to complete reaction between theetherifying agent and the dextran in situ in the yarn, and thereaftertreating the yarn with acetone to activate the ether to adhesivecondition.

9. The method of producing an adhesive cotton yarn which comprisestreating a cotton yarn with an aqueous alkaline solution of dextran,then treating the dextranimpregnated cotton yarn with an aqueousalkaline solution of a benzyl ether of dextran, heating the impregnatedyarn to a temperature of 130 C. to 140 C. to complete reaction betweenthe etherifying agent and the dextran in situ in the yarn, andthereafter treating the yarn with dioxane to activate the ether toadhesive condition.

10. The method of producing an adhesive cotton yarn which comprisestreating a cotton yarn with an aqueous alkaline solution of dextran,then treating the dextranimpregnated cotton yarn with an aqueousalkaline solution of a benzyl ether of dextran, heating the impregnatedyarn to a temperature of 130 C. to 140 C. to complete reaction betweenthe etheritying agent and the dextran in situ in the yarn, andthereafter treating the yarn with benzene to activate the ether toadhesive condition.

11. The method of producing an adhesive cotton yarn which comprisestreating a cotton yarn with an aqueous alkaline solution of dextran,then treating the dextranimpregnated cotton yarn with an aqueousalkaline solution of a benzyl ether of dextran, heating the impregnatedyarn to a temperature of 130 C. to 140 C. to complete reaction betweenthe etherifying agent and the dextran in situ in the yarn, andthereafter treating the yarn with toluene to activate the ether toadhesive condition.

12. The method of claim 7 in which the treatment with the aqueoussolution of the etherifying agent is performed while the yarn is undertension.

References Cited in the file of this patent UNITED STATES PATENTS148,319 Newton Mar. 10, 1874 2,126,936 Wall Aug. 16, 1938 2,203,705Stahly et al. June 11, 1940 2,236,386 Stahly et al. Mar. 25, 19412,344,179 Stahly Mar. 14, 1944 2,486,399 Gagarine Nov. 1, 1949 2.503,624Luaces Apr. 11, 1950

7. THE METHOD OF PRODUCING AN ADHESIVE COTTON YARN WHICH COMPRISESTREATING A COTTON YARN WITH AN AQUEOUS ALKALINE SOLUTION OF DEXTRAN,THEN TREATING THE DEXTRAN-IMPREGNATED COTTON YARN WITH AN AQUEOUSALKALINE SOLUTION OF AN ETHERIFYING AGENT SELECTED FROM THE GROUPCONSISTING OF ALKYLATING AND ARALKYLATING AGENTS, HEATING THEIMPREGNATED YARN TO COMPLETE REACTION BETWEEN THE ETHERIFYING AGENT ANDTHE DEXTRAN IN SITU IN THE YARN, AND THEREAFTER TREATING THE YARN WITH ASOLVENT FOR THE DEXTRAN ETHER TO ACTIVATE THE ETHER TO ADHESIVECONDITION.